glucosides such as sinigrin, alkaloids such as nortropane, flavonoids such as
isorhamnetin and tannins (Alam et al. 2011; Obi et al. 2009).
Sinigrin (2-propenyl-glucosinolate) is the major glucosinolate found in B. nigra;
due to its volatility, it has the ability to provide a pungent aroma as well as taste and
flavour to the extracted oil (Amare et al. 2015; Avato and Argentieri 2015; Talapatra
and Talapatra 2015; Borș et al. 2015; Hirani et al. 2012; Mazumder et al. 2016). In
addition, sinigrin has the ability to produce isothiocyanates by the metabolic activation, which contributes to antitumour activities (Jie et al. 2014). B. nigra has other
types of glucosinolates as well, namely, glucoraphanin, sinalbin (4-hydroxybenzyl),
4-hydroxyglucobrassicin,
glucobrassicin,
4-methoxyglucobrassicin
and
neoglucobrassicin. The production of glucosinolates depends on the availability of
light in the environment in which the plants are grown. It has been observed that
B. nigra grown under dark conditions produce more glucosinolates than under light
conditions (Borș et al. 2015).
The use of mustard and rapeseed meal utilization as a food for domestic animals
has increased during past few decades. Different types of heating and extraction
methods, including toasting and microwave processing, are used in the preparation
of detoxified meals. It has to be highlighted that the main purposes of these
processing methods are to remove the glucosinolates or their hydrolysis products
and combined products such as myrosinase. However, it leads to losses in proteins,
partial removal of glucosinolates and their degradation products and reduced functional or nutritional properties of the detoxified products as well as high processing
costs. Other methods have also been developed to detoxify mustard seeds, such as
the extraction of glucosinolates with water, using aqueous bases and aqueous
alcohols (Pecháček et al. 2000).
8.6 Health Benefits of B. nigra Seed and Oil
The overall medicinal properties of primarily B. nigra seed and oil are summarized
and presented as a schematic as shown in Fig. 8.2. The properties are discussed
individually along with evidence in Sects. 8.6.1 to 8.6.10.
8.6.1 Antidiabetic Effects and Preventing Hepatic and Renal
Damage
B. nigra seeds have been revealed to possess antidiabetic effects. This ability has
been proven in streptozotocin (STZ)-induced diabetic animals, where the rats were
treated with the aqueous extract of B. nigra seeds leading to reduced serum glucose
levels. The extracts also helped in maintaining reduced glycosylated haemoglobin
and serum lipids (Anand et al. 2007). In a follow-up study by Anand et al. (2009)
196
H. K. S. De Zoysa and V. Y. Waisundara
isorhamnetin and tannins (Alam et al. 2011; Obi et al. 2009).
Sinigrin (2-propenyl-glucosinolate) is the major glucosinolate found in B. nigra;
due to its volatility, it has the ability to provide a pungent aroma as well as taste and
flavour to the extracted oil (Amare et al. 2015; Avato and Argentieri 2015; Talapatra
and Talapatra 2015; Borș et al. 2015; Hirani et al. 2012; Mazumder et al. 2016). In
addition, sinigrin has the ability to produce isothiocyanates by the metabolic activation, which contributes to antitumour activities (Jie et al. 2014). B. nigra has other
types of glucosinolates as well, namely, glucoraphanin, sinalbin (4-hydroxybenzyl),
4-hydroxyglucobrassicin,
glucobrassicin,
4-methoxyglucobrassicin
and
neoglucobrassicin. The production of glucosinolates depends on the availability of
light in the environment in which the plants are grown. It has been observed that
B. nigra grown under dark conditions produce more glucosinolates than under light
conditions (Borș et al. 2015).
The use of mustard and rapeseed meal utilization as a food for domestic animals
has increased during past few decades. Different types of heating and extraction
methods, including toasting and microwave processing, are used in the preparation
of detoxified meals. It has to be highlighted that the main purposes of these
processing methods are to remove the glucosinolates or their hydrolysis products
and combined products such as myrosinase. However, it leads to losses in proteins,
partial removal of glucosinolates and their degradation products and reduced functional or nutritional properties of the detoxified products as well as high processing
costs. Other methods have also been developed to detoxify mustard seeds, such as
the extraction of glucosinolates with water, using aqueous bases and aqueous
alcohols (Pecháček et al. 2000).
8.6 Health Benefits of B. nigra Seed and Oil
The overall medicinal properties of primarily B. nigra seed and oil are summarized
and presented as a schematic as shown in Fig. 8.2. The properties are discussed
individually along with evidence in Sects. 8.6.1 to 8.6.10.
8.6.1 Antidiabetic Effects and Preventing Hepatic and Renal
Damage
B. nigra seeds have been revealed to possess antidiabetic effects. This ability has
been proven in streptozotocin (STZ)-induced diabetic animals, where the rats were
treated with the aqueous extract of B. nigra seeds leading to reduced serum glucose
levels. The extracts also helped in maintaining reduced glycosylated haemoglobin
and serum lipids (Anand et al. 2007). In a follow-up study by Anand et al. (2009)
196
H. K. S. De Zoysa and V. Y. Waisundara